Projection television sets are a popular alternative to picture tube television sets, as they provide relatively large viewable screens that cannot be efficiently produced using conventional picture tubes. Projection television sets typically include an enclosure with an optical unit, a mirror, and electronic components for receiving and projecting an image onto a screen assembly mounted on the front of the enclosure.
A typical projection television set 100 is shown in FIG. 1. The projection television set 100 has an optical unit 10 that generally includes a set of projection units 20. Each projection unit projects an image, generally of a single color of light (red, green, or blue), onto the mirror M in the enclosure 105, which focuses the image onto an inside surface of the screen S. Each projection unit 20 includes a cathode ray tube (CRT) 22, a projection lens assembly 45, and a spacer 28 interposed between each respective CRT and projection lens assembly. The projection units 20 are mounted to a bracket 50 in the enclosure 105. The enclosure 105 is typically divided by an internal wall 112 into two compartments, an upper compartment 114 and a lower compartment 116. The internal wall 112 tightly seals the upper compartment 114 from the lower compartment 116 to protect the inside of the upper compartment 114 from dust and other foreign materials. The optical unit 10 is typically mounted in the lower compartment 116, while the mirror M and screen S are mounted in the upper compartment 112. Furthermore, the optical unit 10 typically extends from the lower compartment 116 into the upper compartment through the internal wall 112.
The existing techniques for mounting the mirrors M of projection television sets have their disadvantages. In particular, present methods of mounting the mirrors on the production line is quite time consuming and require special tools and knowledge to accomplish. Therefore, it would be desirable to provide for a more efficient and reliable means for properly mounting the mirrors within the enclosures, and apparatuses for accomplishing those means.